<?php
/**
 * RSS Helper class file.
 *
 * Simplifies the output of RSS feeds.
 *
 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 * @link          http://cakephp.org CakePHP(tm) Project
 * @package       Cake.View.Helper
 * @since         CakePHP(tm) v 1.2
 * @license       http://www.opensource.org/licenses/mit-license.php MIT License
 */

App::uses('AppHelper', 'View/Helper');
App::uses('Xml', 'Utility');

/**
 * RSS Helper class for easy output RSS structures.
 *
 * @package       Cake.View.Helper
 * @property      TimeHelper $Time
 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html
 */
class RssHelper extends AppHelper {

	/**
	 * Helpers used by RSS Helper
	 *
	 * @var array
	 */
	public $helpers = array('Time');

	/**
	 * Base URL
	 *
	 * @var string
	 */
	public $base = null;

	/**
	 * URL to current action.
	 *
	 * @var string
	 */
	public $here = null;

	/**
	 * Parameter array.
	 *
	 * @var array
	 */
	public $params = array();

	/**
	 * Current action.
	 *
	 * @var string
	 */
	public $action = null;

	/**
	 * POSTed model data
	 *
	 * @var array
	 */
	public $data = null;

	/**
	 * Name of the current model
	 *
	 * @var string
	 */
	public $model = null;

	/**
	 * Name of the current field
	 *
	 * @var string
	 */
	public $field = null;

	/**
	 * Default spec version of generated RSS
	 *
	 * @var string
	 */
	public $version = '2.0';

	/**
	 * Returns an RSS document wrapped in `<rss />` tags
	 *
	 * @param array  $attrib `<rss />` tag attributes
	 * @param string $content Tag content.
	 *
	 * @return string An RSS document
	 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html#RssHelper::document
	 */
	public function document($attrib = array(), $content = null) {
		if ($content === null) {
			$content = $attrib;
			$attrib = array();
		}
		if (!isset($attrib['version']) || empty($attrib['version'])) {
			$attrib['version'] = $this->version;
		}

		return $this->elem('rss', $attrib, $content);
	}

	/**
	 * Returns an RSS `<channel />` element
	 *
	 * @param array  $attrib `<channel />` tag attributes
	 * @param array  $elements Named array elements which are converted to tags
	 * @param string $content Content (`<item />`'s belonging to this channel
	 *
	 * @return string An RSS `<channel />`
	 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html#RssHelper::channel
	 */
	public function channel($attrib = array(), $elements = array(), $content = null) {
		if (!isset($elements['link'])) {
			$elements['link'] = '/';
		}
		if (!isset($elements['title'])) {
			$elements['title'] = '';
		}
		if (!isset($elements['description'])) {
			$elements['description'] = '';
		}
		$elements['link'] = $this->url($elements['link'], true);

		$elems = '';
		foreach ($elements as $elem => $data) {
			$attributes = array();
			if (is_array($data)) {
				if (strtolower($elem) === 'cloud') {
					$attributes = $data;
					$data = array();
				} elseif (isset($data['attrib']) && is_array($data['attrib'])) {
					$attributes = $data['attrib'];
					unset($data['attrib']);
				} else {
					$innerElements = '';
					foreach ($data as $subElement => $value) {
						$innerElements .= $this->elem($subElement, array(), $value);
					}
					$data = $innerElements;
				}
			}
			$elems .= $this->elem($elem, $attributes, $data);
		}
		return $this->elem('channel', $attrib, $elems . $content, !($content === null));
	}

	/**
	 * Transforms an array of data using an optional callback, and maps it to a set
	 * of `<item />` tags
	 *
	 * @param array        $items The list of items to be mapped
	 * @param string|array $callback A string function name, or array containing an object
	 *     and a string method name
	 *
	 * @return string A set of RSS `<item />` elements
	 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html#RssHelper::items
	 */
	public function items($items, $callback = null) {
		if ($callback) {
			$items = array_map($callback, $items);
		}

		$out = '';
		$c = count($items);

		for ($i = 0; $i < $c; $i++) {
			$out .= $this->item(array(), $items[$i]);
		}
		return $out;
	}

	/**
	 * Converts an array into an `<item />` element and its contents
	 *
	 * @param array $att The attributes of the `<item />` element
	 * @param array $elements The list of elements contained in this `<item />`
	 *
	 * @return string An RSS `<item />` element
	 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html#RssHelper::item
	 */
	public function item($att = array(), $elements = array()) {
		$content = null;

		if (isset($elements['link']) && !isset($elements['guid'])) {
			$elements['guid'] = $elements['link'];
		}

		foreach ($elements as $key => $val) {
			$attrib = array();

			$escape = true;
			if (is_array($val) && isset($val['convertEntities'])) {
				$escape = $val['convertEntities'];
				unset($val['convertEntities']);
			}

			switch ($key) {
				case 'pubDate' :
					$val = $this->time($val);
					break;
				case 'category' :
					if (is_array($val) && !empty($val[0])) {
						foreach ($val as $category) {
							$attrib = array();
							if (is_array($category) && isset($category['domain'])) {
								$attrib['domain'] = $category['domain'];
								unset($category['domain']);
							}
							$categories[] = $this->elem($key, $attrib, $category);
						}
						$elements[$key] = implode('', $categories);
						continue 2;
					} elseif (is_array($val) && isset($val['domain'])) {
						$attrib['domain'] = $val['domain'];
					}
					break;
				case 'link':
				case 'guid':
				case 'comments':
					if (is_array($val) && isset($val['url'])) {
						$attrib = $val;
						unset($attrib['url']);
						$val = $val['url'];
					}
					$val = $this->url($val, true);
					break;
				case 'source':
					if (is_array($val) && isset($val['url'])) {
						$attrib['url'] = $this->url($val['url'], true);
						$val = $val['title'];
					} elseif (is_array($val)) {
						$attrib['url'] = $this->url($val[0], true);
						$val = $val[1];
					}
					break;
				case 'enclosure':
					if (is_string($val['url']) && is_file(WWW_ROOT . $val['url']) && file_exists(WWW_ROOT . $val['url'])) {
						if (!isset($val['length']) && strpos($val['url'], '://') === false) {
							$val['length'] = sprintf("%u", filesize(WWW_ROOT . $val['url']));
						}
						if (!isset($val['type']) && function_exists('mime_content_type')) {
							$val['type'] = mime_content_type(WWW_ROOT . $val['url']);
						}
					}
					$val['url'] = $this->url($val['url'], true);
					$attrib = $val;
					$val = null;
					break;
				default:
					$attrib = $att;
			}
			if ($val !== null && $escape) {
				$val = h($val);
			}
			$elements[$key] = $this->elem($key, $attrib, $val);
		}
		if (!empty($elements)) {
			$content = implode('', $elements);
		}
		return $this->elem('item', (array) $att, $content, !($content === null));
	}

	/**
	 * Converts a time in any format to an RSS time
	 *
	 * @param int|string|DateTime $time UNIX timestamp or valid time string or DateTime object.
	 *
	 * @return string An RSS-formatted timestamp
	 * @see TimeHelper::toRSS
	 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html#RssHelper::time
	 */
	public function time($time) {
		return $this->Time->toRSS($time);
	}

	/**
	 * Generates an XML element
	 *
	 * @param string       $name The name of the XML element
	 * @param array        $attrib The attributes of the XML element
	 * @param string|array $content XML element content
	 * @param bool         $endTag Whether the end tag of the element should be printed
	 *
	 * @return string XML
	 * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/rss.html#RssHelper::elem
	 */
	public function elem($name, $attrib = array(), $content = null, $endTag = true) {
		$namespace = null;
		if (isset($attrib['namespace'])) {
			$namespace = $attrib['namespace'];
			unset($attrib['namespace']);
		}
		$cdata = false;
		if (is_array($content) && isset($content['cdata'])) {
			$cdata = true;
			unset($content['cdata']);
		}
		if (is_array($content) && array_key_exists('value', $content)) {
			$content = $content['value'];
		}
		$children = array();
		if (is_array($content)) {
			$children = $content;
			$content = null;
		}

		$xml = '<' . $name;
		if (!empty($namespace)) {
			$xml .= ' xmlns';
			if (is_array($namespace)) {
				$xml .= ':' . $namespace['prefix'];
				$namespace = $namespace['url'];
			}
			$xml .= '="' . $namespace . '"';
		}
		$bareName = $name;
		if (strpos($name, ':') !== false) {
			list($prefix, $bareName) = explode(':', $name, 2);
			switch ($prefix) {
				case 'atom':
					$xml .= ' xmlns:atom="http://www.w3.org/2005/Atom"';
					break;
			}
		}
		if ($cdata && !empty($content)) {
			$content = '<![CDATA[' . $content . ']]>';
		}
		$xml .= '>' . $content . '</' . $name . '>';
		$elem = Xml::build($xml, array('return' => 'domdocument'));
		$nodes = $elem->getElementsByTagName($bareName);
		if ($attrib) {
			foreach ($attrib as $key => $value) {
				$nodes->item(0)->setAttribute($key, $value);
			}
		}
		foreach ($children as $child) {
			$child = $elem->createElement($name, $child);
			$nodes->item(0)->appendChild($child);
		}

		$xml = $elem->saveXml();
		$xml = trim(substr($xml, strpos($xml, '?>') + 2));
		return $xml;
	}
}
